Most conventional fluid storing containers tend to be made of metal, which can be easily corroded during its lifetime of use. In order to extend the operational life of these fluid storing containers, galvanic protection may be provided to the inner metal wall surface of the containers to slow the onset of corrosion. This corrosion protection may be achieved by implanting sacrificial anodes into the fluid storing containers. The protection is achieved by way of dissimilar electrochemical potentials between the metal of the anode and the metal of the fluid storing container. In addition, the fluid that is stored (i.e. water) serves as an electrolyte ensuring an electron flow between the anode and the container. The anode metal is electronegative and is generally composed of Mg, Al, or Zn while the fluid container is generally composed of steel thereby resulting in a small electromotive force between the anode and the tank. This electromotive force inhibits the corrosion of metal container by cathodically protecting the metal container, and in turn, the anode is slowly consumed or sacrificed.
One of the main concerns of the water heater manufacturer is the life of the anode. The life of an anode is inversely dependent on the amount of electromotive force it generates to cathodically protect the metal container. In many fresh water supplies, particularly in water supplies with high mineral content, the electromotive force generated by the anode is quite high resulting in a quicker depletion of the anode. In order to control the electromotive force of generated by an anode, resistor devices have been incorporated into the anode, and electrically connected between the anode and the protected fluid container, to automatically control the amount of electromotive force generated by the anode thereby increasing the operational life of the anode. Although resistor coupled anodes tends to have a longer operational life, the construction of this device tends to be complex, the assembly of this device tends to difficult, and the fabrication of this device tends to be expensive. Prior art has attempted to solve the problems listed above by disclosing a sacrificial anode assembly, which comprises of a cylindrical metal anode member having an end retained within a cylindrical plastic insulating sleeve which, in turn, is captively retained with a metal cap portion. In order to regulate the current flow from the anode, a barrel-shaped resistor is incorporated into the assembly and is interconnected between the anode and the cap portions. The cylindrical plastic insulating sleeve has a generally U-shaped groove formed in a closed end, with one leg of the groove extending diametrically across a central opening in the sleeve end that receiving a core portion of the anode member, and the other groove leg extending chordwise relative to the sleeve end. The resistor body is received within the chordwise groove leg, and a lead wire of the resistor is extended through the curved and diametrically extending groove portions and spot welded to the core wire portion received in the central sleeve end opening.
Although this method of incorporating the resistor into an anode assembly may reduce the amount of time and cost of assembling such a device, and provides the desired regulation of anode current generation, the structure of the device is still quite complex and difficult to assemble. The proposed assembly need not require any welding/soldering of the resistor wire to the metallic core.
From the foregoing, it can be seen that there is a need to produce a simpler, less complex resistor coupled sacrificial anode devices thereby decreasing the difficulty of assembly of such a device.